Service Differentiation in Software Defined Virtual Heterogeneous Wireless Networks

The proliferation of mobile demands and increasingly multifarious services pose challenges to both the radio access networks (RANs) and the core network (CN). Unfortunately, the traditional networks can hardly meet the increasing requirements. Software-defined network (SDN) and network virtualization (NV) are considered as innovative paradigms to stress these problems. By extending SDN to wireless networks, software-defined wireless network (SDWN) consisting of both RANs and CN can be obtained. In this paper, the RANs and CN of SDWN are virtualized to virtual access points (VAPs) and network slices respectively based on NV technology. Considering the system scenario that a SDWN consists of overlapping RANs, an optimal joint VAP and network slice selection scheme is proposed. To characterize the complicated transmission performance of VAPs and network slices, the concepts of utility function and network calculus are introduced, and the joint utility of VAPs and network slices is formulated based on which the optimal VAP and network slice combination corresponding to the maximal joint utility can be selected. The simulation results demonstrate the efficiency of the proposed scheme.

Wireless network virtualization is an emerging technology that logically divides a wireless network element, such as a base station (BS), into multiple slices with each slice serving as a standalone virtual BS. In such a way, one physical mobile wireless network can be partitioned into multiple virtual networks each operating as an independent wireless network. Wireless virtual networks, as composed of these virtual BSs, need to provide quality of service (QoS) to mobile end user services. Key QoS parameters include buffer queue length, network delay and effective bandwidth, in particular their upper bound forms. This paper presents a QoS model for such a wireless virtual network addressing these parameters. This QoS model considers resources of both physical nodes and virtual nodes and provides a realistic modelling of the delay and bandwidth behaviours of wireless virtual networks. Network calculus (NC), which usually provides finer insight into a system, is utilized to fulfil the modelling task. The numerical results have shown the effectiveness of the proposed model. The model is useful for both off-line network planning and online network admission control.

5G networks are expected to be highly dense and heterogeneous. Building up such a network require a lot of capital investment. Hence, it is essential to optimize the resource utilization, maximize the network availability and minimize the operational cost with acceptable quality of experience(QOE) and quality of service(QOS) parameters. In this research paper, we present a cost effective node allocation method based on traffic forecast in virtual wireless networks(VWN) with grid topology. The problem is formulated using linear programming. Our simulation results show that, it reduces the service provider's operational cost. We propose to use this method as a service in VWN in the Software Defined Networking(SDN) context. An architecture supporting the formulation has also been proposed.

In this paper we investigate the impact of a Relay Node (RN) placement plan on a heterogeneous wireless network called Hybrid Wireless Network with dedicated delay nodes (HWN*) in terms of system capacity, transmission delay and Quality of Service (QoS). A novel HWN* Heuristic RN Placement (HHRP) algorithm, which considers RN assistance & support for radio resource sharing such as inter-network traffic balancing, TD/CDMA soft handover, routing and user mobility has been implemented. A system level simulation is used to quantify the benefits of HWN* using HHRP algorithm over HWN* with other RN placement plans and multi-hop cellular networks. I. INTRODUCTION A heterogeneous wireless network refers to a wireless net- work that is comprised of wireless nodes with different radio access technologies or equipment with different operating systems. For example, it can be a wireless sensor network including bluetooth based radio access and zigbee 802.15.4 based radio access or a hybrid wireless network including cellular access and 802.11b/g based radio access. Specifi- cally for a hybrid wireless network, the increase of cellular communication intensity results in a reduction in cell size, thus much denser clusters are required resulting in increased infrastructure cost and system complexity. Meanwhile, the bursty nature of communication traffic and path loss results in traffic prediction difficulty. A solution must be found to provide effective resource management, congestion control and routing. The hybrid wireless network which incorporates cellular and MANET interfaced RELAY nodes, provides a practical approach for this. Nevertheless, the dedicated relay infrastructure approach can be also be adapted to the emerging wireless sensor network in order to maintain node connectivity, support sensor data aggregation and optimise power consump- tion.

Decision making is the hot topic in business management. Recently, there have been investigations in Call Admission Control (CAC) to handle the handover events in wireless network environments. Wireless networks have been seen to support different handoff mechanisms, in which the user can switch from one wireless network to another such as from IEEE 802.11 to IEEE 802.16. Many wireless standards, such as IEEE 802.16e and IEEE 802.11, have been proposed to satisfy diverse requirements for mobile users.. Several strategies have been proposed to realize seamless handoff in the heterogeneous networks; in this paper, we analyze the performance of some novel intelligent handoff mechanisms with multiple attributes. The mobile set dynamically selects the optimal network and provides the user with high throughput of Quality of Service (QoS) as to minimize the blocking probability of the system in heterogeneous networks. We evaluate some intelligent handoff mechanisms such as Technique for Order Preference by Similarity to Ideal Solutions (TOPOSIS), Simple Additive Weight (SAW), Analytic Hierarchy Process (AHP) and Fuzzy Logic and Grey Relational Analysis (GRA). From the results, blocking probability and dropping rate can be referenced to support better QoS.

Recently, Network Slicing in Radio Access Technologies (RATs) has been proposed as an approach to divide the wireless network infrastructure into isolated logical slices which are defined following their requirements and features in a service-driven way. To the best of our knowledge, the application of Network Slicing has not been explored in IEEE 802.11ah Networks. In this work, we propose a Virtual Network Slicing Broker (VNSB), a Virtual Network Function (VNF) instantiated inside a Software Defined Network (SDN) controller which communicates with an IEEE 802.11ah network Access Point (AP) via a southbound Application Program Interface (API). Based on information obtained by the northbound API, the slicing broker gets the information contained in the slicing templates, which describes the services features and respective Quality of Service (QoS) restrictions. With these data, the slicing broker makes logical slices in the context of the Restricted Access Windows (RAW) which are periodically sent by the AP to the stations (STA) via the Raw Parameter Set (RPS). Since there is no hardware with the IEEE 802.11ah standard available on the market, we validate the proposed solution through extensive simulations in a typical smart city scenario. Results showed the broker capacity to build and manage logical slices per service, respecting the QoS restrictions of each offered service. Moreover, the proposed slicing broker makes use of available resources of neighbor slices reducing delay, packet loss, and efficiently maximizing throughput per slice.

In this paper, we suggest about MIH (Media Independent Handover) supporting fully distributed handover in heterogeneous network based on Open vSwitch and OpenFlow. Although, personal mobile devices which are released recently have more than 2 mobile network interfaces, there is a small chance to utilize them simultaneously. To do this, MIH is suggested to guarantee the quality of application service when terminals of service users move to the other feature of wireless network in heterogeneous wireless network environment. Also, Open vSwitch of software type of various factors in SDN (Software Defined Network) and OpenFlow which has a control function by interacting with Data Path on network switch have arisen as a proposal to utilize wireless interfaces.Thus, in this paper, we experimented changes in packet flow of wireless interfaces. Moreover, we suggest a method of MIH based on SDN to guarantee communication quality of devices which uses more than 2 wireless interfaces.

A new multi-rat scheduling algorithm for heterogeneous wireless networks

The wireless network environment in the future is going to include various heterogeneous wireless networks. In a heterogeneous wireless network environment, vertical handoff processes caused by the movement of users are inevitable. However, the research related to how to achieve seamless vertical handoff and improve QoS guarantees in today's heterogeneous wireless networks is still something to work on. Therefore, this paper proposed the Advanced Vertical Handoff Translation Center (Advanced VHTC) architecture for Wi-Fi/WiMAX heterogeneous wireless networks, aiming to improve the quality of services in heterogeneous wireless networks by means of packet formats translation between heterogeneous wireless networks and the MIH-based seamless vertical handoff mechanism, which cut down the time for vertical handoff and obtain high quality and persistent connection service. Lastly, with the brilliant results of a complete simulation, this paper will show the performance in terms of delay, jitter, packets loss and throughput to prove that the Advanced VHTC for next generation heterogeneous wireless networks can provide good QoS guarantees and obtain persistent transmission with high performance while performing seamless vertical handoff.

In this paper, we investigate the machine learning approaches (sparse Bayesian linear regression (SBLR) and support vector machine (SVM)) for channel state information (CSI) prediction and dynamic radio frequency (RF) slicing for software defined virtual wireless networks in large-scale multi-input multi-output (MIMO) wireless networks. Specifically, a subset of the antennas of virtual wireless networks transmits pilot symbols for estimating the CSI and use the estimated CSI dataset to train and estimate the remaining channels and future CSI for virtual networks using machine learning algorithms. This helps not only to predict the CSI with least overhead and fulfills the service demands of users but also to reduce the power consumption and computation overhead in the network. Predicted CSI is leveraged for RF slicing for virtual wireless networks. Simulation results show that the proposed SBLR for predicting CSI results in lower BER and higher data rate for the wireless users. Furthermore, SBLR outperforms the other approaches when we have sparse CSI information and we need to generalize the prediction process.

Wireless network virtualization (WNV) is considered as a reliable and effective solution to enhance the capacity and resource utilization in emerging 5G cellular wireless networks. WNV supports network sharing and multi-tenancy by allowing application or service providers with limited resources to lease network resources from mobile network operators. Several works in the literature surveyed various aspects of resource allocation and network slicing methods to implement virtualization in wireless networks. In this paper, we focus on economic aspects of WNV and study auction theory as a fundamental tool for designing business models for virtualization of wireless networks, 5G cellular networks in particular. Starting with the concept of WNV in 5G cellular networks, we describe the basic principles and solution approaches in auction theory for heterogeneous and multi-commodity scenarios. Subsequently, we review the recent advances in WNV based on auction models. We conclude by outlining the open challenges and future research directions related to applications of auctions in WNV.

Software-Defined Network (SDN) is one of the most predominant technologies for networking in the existing and next-generation networks. SDN can conFig. , control, protect, and optimize network resources through software. The fundamental benefit of SDN is enabling the application of dynamic management. In addition, the literature shows that partitioning a Software-Defined Wide Area Network (SD-WAN) into several logical networks efficiently will optimize its performance. The main aim of paper is to design an algorithm to slice SD-WAN dynamically into several virtual networks according to the server-clients’ correlation using the Virtual Local Area Network (VLAN). The several virtual networks improve QoS of SD-WAN and reduce its broadcasting domain. The proposed framework consists of two parts. The first part is the management algorithm that finds the best server for each client; then it groups this server with their client in a dedicated logical network. The second part includes creating a VLAN for each logical network in an SD-WAN. The application of the POX controller calculates and maintains the dynamic VLAN, which will be applied by the control plan to slice the topology in the data plan. SD-WAN topology is tested before and after applying VLANs. The results show enhancement in latency by 42.85%, throughput by 4.61%, loss packet by 72% and jitter by 47.86% after applying VLAN. Finally, the greatest gain is reducing the broadcasting ratio by 77.77%. Index Terms— Virtual Local Area Network (VLAN), Software-Defined Network (SDN), Software-Defined Wide Area Network (SD-WAN), Quality of Service (QoS), OpenFlow (OF).

Over the last couple of years, the recent pandemic rendered work operations to be mobile and relied heavily on real-time and traffic-intensive applications such as online classrooms and meetings. Since our working life requires seamless mobility and stable wireless connectivity, heterogeneous wireless networks gain more attention as key infrastructures to fulfill communication needs. Intelligent handover decision deems necessary to select the appropriate wireless network. An intelligent mechanism such as fuzzy logic proves to enhance such decision-making. Different membership functions used in a fuzzy inference system contribute to different network selection performances. This work evaluates different fuzzy membership functions, hence appropriate membership functions can be used in the design of fuzzy-based network selection mechanisms for heterogeneous wireless networks.

Many studies have shown that Vegas TCP has a better throughput and stability than Reno TCP in homogeneous networks with a single TCP flavor, but performs less well in heterogeneous networks in which two TCP flavors coexist. The progressive behavior of Reno TCP and the conservative behavior of Vegas TCP cause a bias when they are used simultaneously, and thus Vegas TCP fails to obtain a fair share of the bandwidth. This paper examines the origins of this bias and proposes a threshold-based congestion control mechanism designed to alleviate the resulting unfairness problem. The simulation results show that the proposed scheme achieves a higher throughput than the conventional Vegas TCP scheme and preserves the stability of the conventional scheme when used in heterogeneous wired and wireless networks.

Network emulation is an essential tool to evaluate network protocols and network security technologies. Leveraging on the cloud computing services, a hybrid network emulation platform integrating virtual and physical networks is proposed in this paper. With cloud services, heterogeneous and scalable virtual networks can be built. By accessing physical networks, the whole platform will be improved with high precision. Software defined network (SDN) switch is applied in the platform. With its OpenFlow protocol, packet flows can be controlled with flexibility to support transparent network emulation. Meanwhile, SDN switches cooperate with physical switches to provide the platform with experiments isolation and reconfigurability. The attributes of any virtual-physical link are also considered to emulate real networks with latency, bandwidth and loss rate. Extensive experiments proved that the proposed platform is capable to emulate networks with scalability, transparency, and can further support multiple experiments isolation.